


Awkward matings

by TyFell (tygirl9)



Category: Supernatural
Genre: Alpha Castiel (Supernatural), Alpha Castiel/Omega Dean Winchester, Alpha/Beta/Omega Dynamics, M/M, Mpreg, Omega Dean, Omega Gabriel, Omega Sam, idiots to lovers
Language: English
Status: In-Progress
Published: 2019-04-21
Updated: 2019-04-21
Packaged: 2020-01-23 08:54:59
Rating: Mature
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 1,969
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/18546472
Author URL: https://archiveofourown.org/users/tygirl9/pseuds/TyFell
Summary: Cas has liked Dean since he was a child, but thought his best friends brother would never like him back. But what happens when he presents?





	Awkward matings

**Author's Note:**

> There will hopefully be at least one more chapter. I don't know if I will make more after that, but if I do I'll try and make it mostly standalone.

Cas sighed, trying not to stare at Sam's older brother. Sam and Dean were both omegas, and he'd known them since kindergarten when he'd given Sam some of his cookies. From the first time he'd met Dean he'd had a giant crush on him, and it hasn't changed. He wished Dean would show if he feels the same way or not, but maybe he was waiting to see how he presented? 

Sam had presented months ago, and Cas should be presenting within the next month. He was fifteen, almost 16, and it almost always was around the 16th birthday that people presented, and he wasn't sure what he'd end up as. He'd been worrying for a bit, his oldest brother, Michael, was an alpha, but his other two brothers were omegas. 

He hadn't been paying attention to the conversation around him, but he saw his brother, Gabriel, pouting, so he assumed he'd tried flirting with Sam again just for his friend to not realize. 

“So, what are you guys doing for Cas’ birthday? Sam hasn't mentioned anything.” Dean asked, trading Sam's chips for his veggies. Their step father, Bobby, always insisted packing them the same things even though he knew they traded. 

“Mom and dad have to go on a business trip, so Cas and I decided to just see if you two can come over to keep us company. That way Cassie has something to do on his birthday other that awkwardly seeing Michael and Lucifer. There's a bigger party planned later, but you know.” 

Dean grinned. “So ask your parents. Dad and Bobby will be fine with it, and we'll ask them tonight for good measure. Maybe I'll drive us to pick up a cake and Cas can pick out something for his gift while we're there? And should make dinner or just pick something us, Cas?”

“Think you can make your Alfredo? It's one of my favorites, and I can't even get other versions much because mom hates it.”

“That should work. Maybe if you haven't presented yet by then I'll make some extra and one or two other things to freeze for you, that way you don't have to deal with just eating crackers or whatever other shit someone grabs you.”

“That's super helpful. If I didn't have these two around for my heat I wouldn't have made it, you know? Well, I probably would've, but it wouldn't have been pleasant. It sucked the first day before you called them and told them that I was in heat. But when they got to me, especially with food, it was easier. If you go into heat we'll all be there for you. If it's rut, we'll all be there for you, through text.”

Cas laughed, happy his friends had his back. 

\---

The four guys were at the store, looking at the cakes, Sam and Cas debating between Spiderman or a Rapunzel cake. Cas had automatically gravitated towards a character cake since his parents always went fancy instead of what the kids liked. Dean and Gabe both had a cart, they had convinced their parents to leave them money for food, instead of having to rely on what they have someone buy them, so they were paying for most of the food while Dean and Sam were buying the cake and Cas’ present. 

“I really can't resist the Rapunzel one. Reminds me of Dean too much.” Cas grinned and he, Sam, and Gabriel laughed. Dean was blushing, and Cas couldn't help but think he looked so cute. 

“Hey! Just because I'm blonde with green eyes doesn't mean I look like Rapunzel!” His face turned into a pout, and Cas had to resist the urge to kiss him. He put the Rapunzel cake in the cart, and Gabe grabbed some cookies. They went and grabbed things for Dean to cook, and a few more snacks, before heading to the craft section. 

Cas grabbed a few cheaper brushes and canvas, not the stuff he'd normally use for bigger paintings, but for experiments and testing things that he gets later. They headed to check out, before going back to the house. 

\--

After Sam and Gabe went off to bed, Dean was cooking the extras to freeze for Cas, and Cas was sitting with him keeping him company. Dean had said he should head off to bed a few times, but Cas insisted he was fine, he wasn't tired…. But here he was, sleeping at the table. As Dean finished separating servings, he started to smell something. He put the food in the freezer, before sniffing the air again. 

It wasn't something in the fridge, and didn't seem to be something of the counter… wait. Was it… it was coming from Cas? Fuck, he was presenting. And from what he could smell it seemed he was presenting as an alpha. 

Fuck, what should he do? If he woke him up he'd probably try and jump him. But could he handle waiting for him to come off the wave to talk to him? He'd realized he had feelings for him when he'd presented, but he thought Sam liked him so he'd decided not to mention it. Recently Sam had told him he doesn't like Cas, he liked Gabe, but that still left him not wanting to make things awkward with his brothers potential mates brother. 

He'd started pacing, debating what to do, and then he heard it. Cas mumbled in his sleep, and it took him a second to realize what he was saying. 

Was he… was he saying Dean? 

Was Cas, Cas who was presenting, moaning his name in his sleep? 

He needed to go talk to Sam. He hurried to the media room, where they were setting up to sleep tonight, and shook Sam awake. It took a second for his brother to wake up, but when he did Dean couldn't wait to ask. 

“Has Cas ever mentioned if he likes me?” 

“Wah?” Sam groggily moaned out, but before he and Dean could continue talking Gabriel spoke up. 

“Cas is in love with you, why? What happened?” 

Dean turned to look at him, and started blurting.

“Cas is presenting, he's an alpha, and I've had a crush on him since I presented but didn't want him to decide to mate me just because I was there, but he moaned out my name in his sleep? And I don't know what to do?” 

“Well, you both like each other. Why not mate? Sam and I can tell our families, and Cas would be happy. He may freak out at first, but when he realizes you wanted to mate him he'll be happy. Just transfer the food into Cas’ room fridge first, and the packs of water in the pantry.” The seventeen year old rolled onto his back, looking over at Dean upside down. “Honestly, I heard mom and dad speculating when you would get together anyways.”

Dean was gaping, not unlike a fish, and Sam couldn't help but laugh. “Yeah, Dad and Bobby had a similar conversation, but they included me in it. Dad said you'd be each other's second mates. Bobby said you guys would meet again after college. I said I was surprised you hadn't already started dating.” 

“Even if I wasn't nervous about making things awkward, I'm not into other omegas like you two. I like alphas, and Cas is the only one I liked that wasn't already an alpha, you know? And I had a feeling he'd be one, but I still wasn't sure.”

“Really Dean. If you like him and want to do it, take the chance. He's told both of us he likes you, and it's obvious in other ways, too. But you know him, he's not gonna get the courage to ask you without knowing you like him, and he's oblivious.” Sam laughed, not noticing Gabe looking a Dean as if he was a camera on the office. “Plus it would stop all the other omegas from trying to get with him when he goes back to school. Wealthy, nice looking alpha? You know a lot of them will be all over it, even though they've been shitty to him since we were kids.” 

At that Dean had pretty much made up his mind. “Think you guys can carry them to his room so that this goes faster? And do you have a scarf I can borrow, Gabe? I'd borrow one of Cas’, but, you know.”

The two nodded, standing, before Gabe headed towards his room to get both the other omegas scarves. “Just in case. I'll be fine, I'm his brother and there have never been any leanings, but I know Sam and Cas wouldn't want to accidentally mate.” 

The brothers nodded, and pulled the scarves around their noses, and Sam went to Cas’ room, and Dean and Gabe went over to the kitchen to start bringing over the supplies. It took a half an hour, because they were trying not to wake Cas up yet, but they did have a bit of a scare when Cas decided to shift so his head faced the other way. 

But now, now was the time. Gabe and Sam had moved themselves into Gabriel's room, and Dean was about to wake up Cas, soon to be his alpha. 

He was almost guaranteed to be mated by tomorrow. Holy fuck, he and Cas were about to do this, about to spend Cas’ first rut together. He was nervous, but steeled himself. He could do this. All he needed to do was wake Cas up, and get them to the alphas room. 

He moved to the table, and brought his hand up to run through Cas’ hair. It was already a mess, and he knows it'll be even worse after the three days it'll take them to finish. “Hey, Cas, alpha, it's time to go to your room.” 

As Cas stirred, obviously affected by smelling the Omega, and looked towards him, Dean backed up and offered his hand. “Let's go to your bed, alpha. That way you have me all to yourself.” 

Cas stood, in a daze as he was in his rut, but his mind worked just enough that as he took Dean's hand he spoke. “Dean? I must still be dreaming.” He followed as Dean walked. “I should've told you before I presented, before my birthday. Maybe then I could've gotten a birthday kiss.”

Dean laughed at that. “Well, alpha. It's not a dream. I'm here, I'm real, and if you'll have me I'd be overjoyed if you'd mate me. Plus, your birthday isn't over yet. Once we get to your room, I'll kiss you all you want.”

The alpha let off a happy scent, and Dean felt himself being lifted. Cas carried the Omega to his bedroom, forgetting to lock the door Dean noted, and laid him on the bed, before stripping off his tank top and sweats. Dean watched as he took off his t shirt and pajama pants, slowly. Soon he was left in his panties and Cas was naked, on display. 

Dean pulled the alpha down to kiss him, and when they pulled apart they were both grinning like idiots. 

Cas groaned, and Dean smiled, pulling his panties off. “Let me rub a bit, make sure I'm wet enough. Then you can get in me.” 

Dean reached down, rubbing at his dick. He was already pretty slick, but needed to get himself to leak. It wasn't long before he felt it slipping from his hole, and he knew the alpha could tell, too. Cas kissed at his neck, the spot where he'd bite soon to mate them. 

“Are you ready, my Omega? I don't know how long I can wait…” 

Dean kissed the side of his head. “Do it, alpha. Let's mate.”


End file.
